Update GameCollectionConfig.ini

[GrantBartlett]

Remove prefixed cncnet- to avoid confusion.

[Starkku]

Main reason the prefixes were used was because GameSurge does not allow registering channels using that prefix by anyone not CnCNet staff, which for vast majority of users is better because they won't bother with registering anyway and it prevents malicious actors from doing so. That said I can remove the prefixing if it indeed causes confusion or issues for or with CnCNet operations and staff.